COVID-19, the infectious disease caused by SARS-CoV-2, is rapidly affecting humans around the globe. While initial epidemiological data have focused on cases that resulted in severe respiratory disease seen predominantly in adults, little information regarding the infection burden in children is available. This is complicated by the observation that many virologically confirmed cases in children are asymptomatic (Dong et al, Pediatrics, PMID 32179660). Undocumented, and likely infectious, cases could result in exposure to a far greater proportion of the community than would otherwise occur. Indeed, it has been proposed that undocumented (or silent) infections are the source for almost 80% of documented infections (Li et al, Science, PMID 32179701); thus, it is critical to determine the silent and symptomatic infection rate in children. The purpose of this project is to develop, implement, and report on a surveillance study that will enroll and prospectively observe eligible children who are current participants in NIH/NIAID/DAIT-funded pediatric research studies and their family members. Many of these studies are focused on populations of children with asthma or other atopic conditions. The primary objective of this study will be to determine the incidence of SARS-CoV-2 infection (detection of virus in nasal secretions and stool and antibodies to the virus in blood) over time in children and their household contacts (caregivers and siblings).